Base surge in recent volcanic eruptions
Base surge in recent volcanic eruptions
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最近火山喷发的基数激增
DOI：
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发表时间：
1967
期刊：
影响因子：
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通讯作者：
J. Moore
中科院分区：
文献类型：
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作者：
J. Moore
在比基尼热核海底爆炸中首次发现的基础浪涌是一种环状的基础云，它从垂直爆炸柱的底部以密度流的形式向外扫去。基底涌浪在浅层地下试验爆炸中也很常见，它是由膨胀的气体形成的，这些气体首先垂直喷出，然后在火山口边缘继续膨胀（在水下爆炸中以一个大的孤立波为代表），从中撕裂喷出，并提供充满气体的密度流，这就是涌浪云。这种水平移动的云通常具有超过50米每秒的初始速度，并且可以携带碎屑物质许多公里。基涌是最近许多浅层、海底和潜水火山爆发的共同特征。它们以极快的速度运输火山灰、泥浆、砾石和石块，通常会产生沙尘，推倒树木和房屋，在爆炸一侧覆盖泥浆，并在超出抛射轨迹限制的距离上沉积喷射物。在靠近喷发中心的地方，基底涌浪可以侵蚀径向通道，沉积具有沙丘型层理的物质。
A base surge, first identified at the Bikini thermonuclear undersea explosion, is a ring-shaped basal cloud that sweeps outward as a density flow from the base of a vertical explosion column. Base surges are also common in shallow underground test explosions and are formed by expanding gases which first vent vertically and then with continued expansion rush over the crater lip (represented by a large solitary wave in an underwater explosion), tear ejecta from it, and feed a gas-charged density flow, which is the surge cloud. This horizontally moving cloud commonly has an initial velocity of more than 50 meters per second and can carry clastic material many kilometers.Base surges are a common feature of many recent shallow, submarine and phreatic volcanic eruptions. They transport ash, mud, lapilli, and blocks with great velocity and commonly sandblast and knock down trees and houses, coat the blast side with mud, and deposit ejecta at distances beyond the limits of throw-out trajectories. Close to the eruption center, the base surge can erode radial channels and deposit material with dune-type bedding.